Comparison of Cerebral ECD Perfusion in Patients with Dementia with Lewy Bodies and Parkinson’s Disease Dementia

AbstractDementia with Lewy bodies (DLB) and Parkinson’s Disease Dementia (PDD) are closely related neurodegenerative conditions within the Lewy body spectrum. The relationship between DLB and PDD remains debated, with ongoing discussion about whether they are distinct diseases or different manifestations of the same disorder. This study aimed to identify differences in cerebral perfusion patterns between DLB and PDD patients. Single-photon emission computed tomography (SPECT) Ethyl Cysteinate Dimer (ECD) imaging was performed on each patient, and relative tracer uptake levels across 47 regions of interest (ROIs) and 240 subregions were analyzed. A two-sided Welch’s t-test was employed to evaluate mean perfusion differences, with results further confirmed through a voxel-wise t-test mapping. After adjusting for multiple comparisons using the Benjamini-Hochberg procedure, no regions showed statistically significant differences at the 0.05 level. However, a few subregions in the visual cortices exhibited p-values just above the significance threshold, with lower mean perfusion observed in PDD patients than those with DLB. Validating these findings in larger samples could enhance scientific understanding of the differences in the pathology and progression of DLB and PDD.